DETERMINING OFF-SITE CONCENTRATIONS OF VOLATILE PESTICIDES USING THE TRAJECTORY-SIMULATION MODEL

An environmental transport model is described and illustrated that wil l enable the prediction of the mass and/or concentration of volatile p esticides at any depth in the soil profile and at any height in the at mosphere relatively far distanced downwind from agricultural fields. T he theoretical profile shape model is used to determine transport in t he atmosphere and is coupled to the behavior assessment model (BAM) to describe transport in soils. The model outputs include the soil-water concentrations, the surface volatilization rate, the concentration of pesticides in the atmosphere above the field, and the atmospheric con centration at specified distances downwind from the field. The results from this approach can be used in exposure assessment studies to dete rmine the risk for individuals living near agricultural fields.